Cancer is a Stem cell Disease

A recent publication by Cristian Tomasetti and Bert Vogelstein contributes important arguments to the discourse on the theory of cancer: “Variation in cancer risk among tissues can be explained by the number of stem cell divisions” They attempt to explain the source of the extreme variation of cancer incidence across different tissues. Some tissue types give rise to human cancers more often than other tissue types, and they explain: “The lifetime risk of cancers of many different types is strongly correlated (0.81) with the total number of divisions of the normal self-renewing [stem] cells maintaining that tissue’s homeostasis.”

Here are some implication of their study:
1. Tissues consist of proliferative units nourished by a stem cell.
2. Some stem cell divisions are affected by random replication errors manifested by random somatic mutations.
3. 65% of cancers might be regarded as (pure) stem cell diseases.
Random replication errors in end cells are eliminated from the unit Random replication errors in stem cells are inherited by stem cells 65% of cancer initiated in the stem are random events they cannot be prevented. Now we learn that therapeutic targets (mutations) vary randomly. How then design a molecule to silence a random mutation? In other words, in 65% cancer targeted therapy will fail and Tomasetti and Vogelstein also “kill” targeted therapy.

Let us turn to an interesting implication of their theory, which they fail to mention. Since cancer is a stem cell disease there exist a mapping between cancers and stem cells:
n[tumor types] = n[stem cell types]

Tomasetti and Vogelstein’s study fails to suggest a cancer treatment.
In reality cancer is a stem cell disease caused by a virus. Silence virus and cancer is cured 1
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